It's illegal alright LOL. You could always use the excuse that the hose fell off however I think it would be a good idea to plug the hose that you remove. So they would only have to look at it to realise what you have done. I'm keen on trying it but I would like to get some idea on whether it can cause any damage as I don't know whether guy that said the bov vent can suck air back in is right or wrong. I don't see how this could be the case as the same thing would be happening to any after market bov with a trumpet. Bain, it's the large return hose off the bov that goes back to the intake pipe. Just don't block off the pipe that goes from near the TB to the bov. So what about the APS , CAPPA bov's then fitted to ther kits? It blows under pressure so how can it suck air back in